Exploitation evidence
Known exploited · CISA KEV listed
Added 2022-03-07. Ransomware campaign use: Unknown.
CISA required action: Apply updates per vendor instructions.
CISA due date: 2022-03-21. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
n/a / VMware vCenter Server
Default status: Not specified
- affected: 7.x before 7.0 U1c
- affected: 6.7 before 6.7 U3l
- affected: 6.5 before 6.5 U3n
n/a / VMware Cloud Foundation
Default status: Not specified
- affected: 4.x before 4.2
- affected: 3.x before 3.10.1.2
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.88012,
"percentile": 0.99768
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.88012,
"percentile": 0.99767
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.88012,
"percentile": 0.99767
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.88012,
"percentile": 0.99767
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.88012,
"percentile": 0.99767
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.88012,
"percentile": 0.99767
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.88012,
"percentile": 0.99766
}06 Nov 2026, 00:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
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"timestamp": "2024-02-16T16:16:46.429372Z",
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}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.88012,
"percentile": 0.99766
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.88012,
"percentile": 0.99764
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.88012,
"percentile": 0.99764
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2021-21973",
"cwes": [
"CWE-20",
"CWE-918"
],
"dateAdded": "2022-03-07",
"dueDate": "2022-03-21",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://nvd.nist.gov/vuln/detail/CVE-2021-21973",
"product": "vCenter Server and Cloud Foundation",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "VMware vCenter Server and Cloud Foundation Server contain a SSRF vulnerability due to improper validation of URLs in a vCenter Server plugin. This allows for information disclosure.",
"vendorProject": "VMware",
"vulnerabilityName": "VMware vCenter Server and Cloud Foundation Server Side Request Forgery (SSRF) Vulnerability"
}